When I came on board with this brand in December 2024, the Klaviyo account was technically functional but running inefficiently. A large, under-segmented list was driving up billing costs, and the automation layer wasn't pulling its weight. The account was on a plan that cost more than it needed to — and the results didn't justify it.
The first month was focused on fixing that.
The Klaviyo Cost Problem
Klaviyo bills based on active profiles. This brand had 105,932 profiles sitting against a 135,000-profile plan — many of them inactive and unengaged, inflating the bill without contributing anything to revenue. On top of that, email sends were close to plan capacity at 98%, which meant paying for volume that wasn't translating into meaningful engagement.
By tightening segmentation and cleaning the list more aggressively, we were able to move to a smaller plan. The result: Klaviyo costs dropped by more than $2,100 USD per month — less than half of what it was before.
What Happened to Performance
This is usually where brands get nervous. Sending to fewer people feels like leaving money on the table. In practice, the opposite happened.
Despite sending campaigns to 34% fewer recipients in December, unique opens were actually up 8% compared to November. Engagement held. Revenue held. The emails were reaching people who were actually going to open them, which is what matters both for performance and for long-term deliverability.
By January, flow revenue was up 34% and the Welcome Flow alone was generating £8.06 per recipient. By March, that had climbed to £12.50 per recipient as the flow content was updated and zero-party data segmentation was added — splitting subscribers into gym and streetwear audiences for more relevant messaging.
The updated email designs also contributed. The initial welcome email saw 3x the click rate after the redesign. Small changes in layout and content hierarchy compound across thousands of sends.
The Numbers Across Four Months
December 2024: Klaviyo plan cost cut by $2,100+/month. Unique opens up 8% despite 34% fewer campaign recipients.
January 2025: Flow revenue up 34.3% month-over-month. Mobile pop-up submit rate up 3%, adding ~350 new sign-ups per week after separating mobile and desktop forms.
March 2025: Welcome Flow at £12.50 revenue per recipient. Flow revenue at 26% of total attributed email revenue. Klaviyo plan reduced a further ~$900 by removing excess profiles.
Throughout, deliverability stayed stable — open rate consistently above Klaviyo's 33% threshold, bounce rate and unsubscribe rate both within safe limits.
Why It Worked
Cutting list size and reducing send volume only works if the segmentation is right. Sending to 34% fewer people and seeing more opens isn't a coincidence — it's what happens when you stop carrying unresponsive profiles in every send and let inbox providers see a cleaner engagement signal.
The cost savings came from the same work. A cleaner, more segmented list means fewer active profiles on the plan. Both outcomes came from the same set of decisions.
Work With Us
If your Klaviyo bill feels high relative to what you're getting out of it, that's usually a sign something's off in the setup. A free audit is a good place to start.